Why ISIS's grip on ancient Syrian city spells doom for Middle East

The battle against the Islamic State (ISIS) has been a tale of one step forward, two steps back.

Iraqi forces may have recaptured Saddam Hussein's hometown of Tikrit, and Syrian Kurds may have rebuffed ISIS at Kobane, but the loss of Palmyra will resonate for several reasons.

First, there's the strategic angle. Palmyra sits at a key crossroads linking the Syrian capital, Damascus, to the east of the country. If ISIS controls Palmyra, it has effectively cut eastern Syria off from the capital. Imagine trying to drive from New York to Boston on I-95, for example, if terrorists controlled New Haven.

Then there's the counterterrorism angle.

It has been more than eight months since President Obama announced he would take the fight to the Islamic State. "We will degrade and ultimately destroy [the Islamic State] through a comprehensive and sustained counterterrorism strategy," he declared on Sept. 10, 2014, announcing the beginning of airstrikes against the group responsible for beheading American journalists and aid workers in both Iraq and Syria.

With the Islamic State seizing not only Palmyra, but also Ramadi, the capital of Iraq's Al-Anbar province, it is clear that the terror group is neither destroyed nor particularly degraded.

Such successes bring a windfall of recruitment.

As Osama bin Laden once said, "Everyone loves the strong horse." It may be politically unpalatable, but recent Islamic State gains will bring the United States and the Arab world closer to an unpalatable choice: Intervene with boots on the ground, or acquiesce to the murderous caliphate expanding throughout the Arab world.

Finally, there is the cultural tragedy.

Inspired by a radical Islamist philosophy that considers all ancient artifacts and ruins as un-Islamic and akin to idolatry, the Islamic State has been on the rampage against antiquity.

In Iraq, it has destroyed the ancient cities of Nimrud, Nineveh and Hatra. Palmyra, home to some of the best-preserved, most-striking ruins outside of Rome, will be an even greater loss.

Whether the Islamic State wins or loses, even its brief occupation of Palmyra will resonate for generations.